The Discovery Institute of Seattle has been making a lot of noise
about evolution lately. When some opposed the Melvindale, Michigan
school board's approval of "intelligent design" books such as Michael
Denton's "Evolution: Theory in Crisis" or Philip Johnson's "Darwin on
Trial" for placement in school libraries, the Discovery Institute
(DI) dispatched senior fellow Jonathan Wells to write an editorial in
the Detroit News defending the board's actions. When several
prominent textbook authors and scientists defended evolution's
inclusion in school science texts last month, the DI issued their own
press release expressing their opposition. One theme that's "hot" at
DI is the continual running down of "Darwin's Theory," "Darwinian
evolution," "Darwinism" and so on, while never mentioning "evolution"
or "descent with modification." They act as if recent discoveries in
genetics, DNA, molecular biology and paleontology haven't supported
and expanded our understanding of evolution, when they clearly have.
The DI folks claim the example of natural selection causing color
changes in moths has been completely discredited (it hasn't), and
they claim all "types" of life arose during the Cambrian Explosion.
[See our comments on these arguments and the Melvindale book
flap, below.] Wells will be at the SSE meeting here in
Albuquerque in June.

Melvindale Book Flap

by Kim Johnson and Dave Thomas

There is a controversy in Melvindale, Michigan involving placement
of books critical of evolution in school libraries. Jonathan Wells of
the Discovery Institute in Seattle says it is about censorship and
"fairness." (Detroit
News - Sunday, March 14.) It is really about quality
education. The Melvindale district school board's own resolution
required that books for use in the schools not be about creationism
or "religion in disguise," but instead be fully scientific. But
several books that they approved, and which Wells also wants placed
on the school library shelves, are depressingly un-scientific and
philosophical. These books are littered with scientific-sounding
arguments that often misrepresent or distort the findings of modern
science.

The real force of Wells' argument is an appeal to our sense of
"fairness" and "rights." After all, isn't it only "fair" that our
children have the "right" to " read arguments against it
[evolution] in their school libraries?" Wells even proclaims
that "Anything less would dishonor those before us who fought and
died..." Would Wells be using the same logic and words to defend the
equally silly inclusion of books in school libraries on Satanism or,
perhaps, Lady Chatterley's Lover. After all, isn't it only "fair"
that our "children" have the "right" to read arguments against
Christianity so they can decide if Satanism is worth following? Isn't
it only right that our children read about alternate sexual life
styles so they can make up their own minds about promiscuity? Didn't
our forefathers fight and die for these rights?

Regardless of what Wells claims, this is not a case of fairness or
patriotic rights. In fact, this is not an issue of whether or not a
school district should allow students to see "both points of view."
It is an issue of certain people trying to make a back-door run
around laws and constitutional intent which prohibit specific,
religious advocacy in the public schools. Each and every book that
Wells wants put on library shelves is motivated by the belief in a
very specific religious viewpoint - not by the efficacy of the books
to dispute one of the best standing theories in science. The modern
theory of evolution is on the same level of scientific acceptance as
the theory of gravity, despite what lay critics might say. And since
these books provide twisted "refutations" of almost every facet of
biological evolution, they embody a subtle, yet sinister form of
censorship and mind control.

Do you want your child presented with falsehoods stated as a fact
for the sake of "fairness?" Since when have school libraries not
carefully selected their books so that our children are presented
with the best educational value? Don't you, as parents want the best,
most up-to-date, accurate scientific learning materials available for
your children? Do you really want your children to be misled into
reading high sounding, controversial religious philosophies, full of
scientific errors, as if they were science? Since the libraries use
books chosen by adults, the choice of these misleading books is what
is really unfair, illegal, immoral, and very much against what our
founding fathers really fought for. Fortunately, mainstream science,
the constitution, and the courts agree with us. We applaud the
courage of those folks in Melvindale who also agree and stand up for
what is really fair.

(Lest we be criticized for ignoring the "evidence" Wells and his
Discovery Institute colleagues have been harping on lately, here are
some brief comments on a few of their arguments. Wells states that
" according to the fossil record all the major types of animals
appeared abruptly about 550 million years ago " and "This
'Cambrian explosion' of living things contradicts the branching-tree
pattern predicted by Darwin's theory." But his "types" of animals
don't include amphibians, reptiles, birds, and mammals, which all
came into being hundreds of millions of years after the Cambrian
explosion with extant fossil records showing common decent. And
despite Wells' protestations to the contrary, human embryos do indeed
have gill pouches in one stage of their development. This doesn't
prove that humans evolved, but does indeed support the notion that
humans and fish share some common biological characteristics. [To
the best of our knowledge, none of the biology books Wells refers to
showing greatly exaggerated embryonic development have been used for
many years.] Wells states that all developmental mutations are
harmful. Perhaps he missed the well-reported discovery of a
normally-lethal genetic mutation in a Japanese bacterium that enabled
the lucky little germs to live off of nylon waste alone! Finally,
Wells states that "there is no good evidence that natural selection
works by changing gene frequencies," and claims that the famous
example of adaptation in peppered moths has been totally discredited.
While some observations of the moths have been criticized, it is
wrong to completely discard the moth example, and it is absurd for
Wells to suggest that this was the only evidence for natural
selection. In New Mexico, there is a recent lava flow (less than 2000
years old) where the rock is still very black. Living in this flow
are various squirrels, lizards, etc., which are black to match the
lava color. About 100 miles south is the White Sands National
Monument. Here the squirrels and lizards are white. You don't find
white animals in the lava flow nor black animals in the white sands.
You don't even find either of them in between. The coyotes eat them
up because they stand out from the background too well. Now that
represents what is predicted from natural selection via changing gene
frequencies!)

NMSR Reports, Vol. 5, No. 6, June
1999

Jonathan Wells Replies to April NMSR
Reports

by Dave Thomas

Jonathan Wells, of the Seattle-based Discovery Institute, has sent
NMSR a letter commenting on several of the points raised in the April
1999 issue of NMSR Reports ("Discovery Institute Goes on Warpath,"
"Melvindale Book Flap"). Here is his letter, and our reply.

Dear Mr. Thomas

Your articles referring to me in the April, 1999, issue of NMSR
Reports (Vol. 5 no. 4) have been brought to my attention.

Obviously, we disagree over the merits of Darwinian theory, but
that is not why I'm writing to you. I write in the hope of clearing
up some potential misunderstandings about my position.

Regarding the peppered moths: Kettlewell's experiments supposedly
demonstrated that cryptic coloration and selective bird predation are
the principle causes of industrial melanism were discredited by (a)
findings in the 1960's and 1970's that other factors (such as
migration and non-visual selection) had to be invoked to account for
observed geographical distributions, (b) reports that the rise and
fall of melanism were not correlated with lichen cover on tree trunks
in the U.S. or many parts of the U.K., (c) research in the 1980's
showing that peppered moths in the wild do not normally rest on tree
trunks (where Kettlewell conducted his experiments), and (d)
revelations that all photographs of peppered moths on tree trunks
have been staged, either by manually positioning live moths or by
pinning or gluing dead ones.

I do not deny that selective bird predation may have been one
factor (among several) in the rise and fall of industrial melanism in
peppered moths, and I do not question the integrity of Kettlewell or
others who did the research. I do, however, object to the fact that
textbooks continue to give students the impression that Kettlewell's
experiments demonstrated empirically that industrial melanism is a
simple case of natural selection. I also find it unacceptable that
many of those same books continue to contain staged photos of moths
on tree trunks, ten years after biologists learned that is not where
they naturally rest. I consider this a misrepresentation of the truth
which makes for bad science education.

Regarding the Cambrian explosion: It's true that in my Melvindale
op-ed piece I wrote that "all the major types of animals" arose in
the Cambrian, by which I meant the major animal phyla. There is no
substantial controversy over this among paleontologists. I used
"major types" instead of "phyla" because of the audience I was
addressing, but this usage is not unique among science writers. As
you correctly point out, the various classes of vertebrates arose
later; but the chordate phylum is represented in the Cambrian
fauna.

Regarding gill slits in embryos: human embryos do not have gill
slits. They have pharyngeal arches and pouches (ridges and folds in
the neck region). Only in fish and amphibians do these later develop
into gills; in other vertebrate classes they never take on any of the
morphological or physiological attributes of gills, but develop into
other, unrelated structures. Calling pharyngeal pouches "gill slits"
in human embryos is reading Darwinian theory into the evidence.

Many current biology textbooks use distorted pictures of
vertebrate embryos to convince students that vertebrates share a
common ancestor. See, for example, the latest edition of Miller and
Levine's BIOLOGY, one of the most widely used high-school texts.

Regarding developmental mutations: I do not deny that some
mutations are beneficial, e.g. mutations contributing to antibiotic
or insecticide resistance, or enabling bacteria to grow on novel
substances (such as the example you give of the nylon-waste-eating
bacteria). These are not "developmental mutations," however, since
bacteria do not develop. Saturation mutagenesis screens in
multicellular organisms such as fruit flies, nematode worms and
zebrafish, which produce all possible developmental mutations, have
never found any that are beneficial.

Regarding natural selection: I do not claim that peppered moths
are the only example of natural selection; I claim that they may be
the only good example above the molecular level of a change in gene
frequencies due to natural selection. Certainly, there are plenty of
examples of this at the molecular level (e.g., antibiotic and
pesticide resistance). But in most of the classic examples of natural
selection above the molecular level (e.g., Darwin's finches, Hawaiian
Drosophila, and the squirrels and lizards you cite), the genetic
basis is unknown. If you know of a good example I've missed, I would
stand to be corrected on this.

Some of these points may sound like technicalities. But I try to
be very careful about what I claim. If any claim I make is
inaccurate, which is to say contrary to the evidence, I will correct
it. I prefer to base my claims on actual evidence, rather than on
what Darwinists assure me is the case.

I look forward to attending the SSE conference in June. Perhaps
I'll see you then? Sincerely,

Jonathan Wells, Ph.D.

Department of Molecular & Cell Biology

University of California, Berkeley

and

Center for Renewal of Science and Culture Discovery Institute,
Seattle

April 21, 1999

DAVE THOMAS, KIM JOHNSON
REPLY

Dear Dr. Wells:

Thank you for agreeing to have your letter printed in this issue
of NMSR Reports. You brought up several interesting points. Here are
our responses.

Regarding the peppered moths: This turns out to be a rather
complex issue. Michael Majerus, an expert on the peppered moths,
recently published a book about them entitled Melanism: Evolution in
Action (Oxford, Oxford University Press, 1998). One of Majerus' main
points, in a chapter entitled "The Peppered Moth Story Dissected," is
that "The case of the peppered moth is undoubtedly more complex and
fascinating than most biology texts have space to relate." Elsewhere,
he states "The findings of these scientists show that the
précised description of the peppered moth story is wrong,
inaccurate, or incomplete, with respect to most of the story's
component parts. When details of the genetics, behavior, and ecology
of this moth are taken into account, the resulting story is one of
greater complexity, and in many ways greater interest, than the
simple story that is usually related." But Majerus is not attacking
the basic hypothesis that industrial melanism is due to birds eating
more of the moths that stick out against the background; in other
words, that the shift in coloring of the moth population is due to
natural selection. In fact, Majerus himself pointed out recently that
"it is the text book précised account of the peppered moth
story that I criticize, not the scientific accounts published in peer
reviewed scientific journals." (Personal communication, to Donald
Frack, posted on Internet April 6, 1999.) But most critical to this
discussion is Majerus' conclusion: "Of all the people I know,
including both amateur and professional entomologists who have
experience of this moth, I know of none who doubts that differential
bird predation is of primary importance in the spread and decline of
melanism in the peppered moth." (Ibid.) This is, of course, a very
different conclusion than that drawn by Jonathan Wells :
"Kettlewell's experiments supposedly demonstrated that cryptic
coloration and selective bird predation are the principle causes of
industrial melanism were discredited..."

Regarding Wells' specific points about the moths:

(a) findings in the 1960's and 1970's that other factors (such as
migration and non-visual selection) had to be invoked to account for
observed geographical distributions

It turns out that detailed models of peppered moth evolution have
been refined with inclusion of effects besides differential bird
predation, such as migration. But the effects of these secondary
mechanisms were generally slight. Researchers found that the only
significant such factor was migration, but that even that was much
less important than bird predation. So the fact that other factors
were "invoked" does not alter the basic conclusion that melanism in
the peppered moths demonstrates natural selection in action.

(b) reports that the rise and fall of melanism were not correlated
with lichen cover on tree trunks in the U.S. or many parts of the
U.K.

This is not a universally accepted conclusion. For example,
Majerus states "Although Grant and Clarke argue that lichen growth
has not increased since the clean air acts, others (see for example
Cook et al, 1990, Melanic moths and changes in epiphytic vegetation
in north-west England and north Wales, Biol. J. Linn. Soc., 39,
343-354) show that the lichen flora has increased subsequent to
antipollution legislation, and their has been a corresponding
increase in the pale form of the peppered moth." (Ibid.)

(c) research in the 1980's showing that peppered moths in the wild
do not normally rest on tree trunks (where Kettlewell conducted his
experiments)

Wells refers to researchers who found that the moths sometimes
preferred resting sites besides tree trunks, such as under branches
high in the canopy. Two points are important here. Point (1): "Do not
normally rest" is not the same as "never rest." Consider the
following numbers of moths found resting in various sites between
1964 and 1996 (Majerus 1998, Tables 6.1 and 6.2, page 123): In the
wild, 32 peppered moths were found on exposed trunks, unexposed
trunks, and trunk/branch joints, while 15 were found on branches
alone. In the vicinity of light traps, another 135 were found
associated with trunks, and 20 with branches alone, for totals of 168
associated with trunks, and 35 with branches alone Clearly, Wells'
implication (stated explicitly elsewhere, for example the Detroit
News, March 14, 1999) that peppered moths do not rest on tree trunks
is simply not supported by the available data. Point (2): Majerus and
others have performed new experiments, in which moths were marked and
released, allowed to rest wherever they wanted (trunks or not), and
then recaptured (if possible). The numbers of moths recaptured were
different in polluted woods then in unpolluted woods, again
supporting the differential bird predation hypothesis, i.e. that
moths that blend in better with available backgrounds tend to have a
better chance of survival.

(d) revelations that all photographs of peppered moths on tree
trunks have been staged, either by manually positioning live moths or
by pinning or gluing dead ones.

First, Majerus' 1998 book contains pictures of moths resting on
tree trunks of their own accord, directly contrary to Wells' claim
above that 'all' such photographs have been staged. Secondly, the
purpose of such photographs is to illustrate crypsis (blending in
with the background), not the "normal" resting place of the moths. Of
course, if photographs have been staged, mention should be made of
that, but that should not detract from the usual purpose of the
photographs (demonstration of crypsis).

Wells' conclusions regarding the peppered moth example are
strongly disputed by several experts in the area. In Majerus' words,
"The case of melanism in the peppered moth is one of the best
examples of evolution in action by Darwin's process of natural
selection that we have. In general it is based on good science, and
it is sound." (Personal communication, to Donald Frack, posted on
Internet March 30, 1999.)

Regarding the Cambrian explosion: When Wells stated that "all the
major types of animals appeared abruptly about 530 million years ago,
in a geological period known as the Cambrian" (the Detroit News,
March 14, 1999), he was careful not to be too precise about his
definition of "types." The lay reader might think of these types as
specific - for example, a "rabbit type" or a "shark type." Wells
acknowledges that the "types" are indeed phyla, major groups of
animals. There are still two problems here. First, in the Cambrian,
the representatives of the "vertebrate phylum" were squiggly little
creatures like amphioxus with a fledgling backbone (notochord).

Amphioxus

If all the vertebrates since then (brontosaurus, trout, whales,
humans, to name just a few) are simply "variations within a type," as
Wells apparently suggests, then it appears that Wells is about 90%
"evolutionist." And if these striking vertebrates are more than just
"variations within a type," then what was Wells trying to say about
all major "types" appearing in the Cambrian? Secondly, not all phyla
first appear in the Cambrian. Bryozoan fossils are abundant in New
Mexico, but the phylum Bryozoa
doesn't appear until the Ordovician. And one phylum is
all it takes to refute the statement that "all the major types of
animals appeared abruptly in the Cambrian."

Furthermore, the "explosion" itself could have lasted from ten to
twenty million years. In fact, Stephen Jay Gould has a marvelous
essay in Ever Since Darwin (W.W. Norton & Co., 1977) on the
hypothesis that the Cambrian "Explosion" was simply the log phase of
a sigmoidal (S-shaped) growth curve of the first multi-celled
organisms in a rich medium of bacteria and algae. (The rapid
appearance of new species in the Cambrian is similar to growth curves
of bacteria placed into Petri dishes full of nutrients. The initial
growth is slow at first, and then increases rapidly (log phase), and
finally levels off as niches are filled. In this analogy, the first
multi-celled creatures replace the bacteria, and the bacteria and
algae themselves becomes the nutrient mix.)

Regarding gill slits in embryos: In our editorial in the April 99
NMSR Reports, we stated that "... human embryos do indeed have gill
pouches in one stage of their development. This doesn't prove that
humans evolved, but does indeed support the notion that humans and
fish share some common biological characteristics." We agree with Dr.
Wells that it would be improper to call these pouches "gill slits,"
and we point out that we simply did not do so, contrary to his
assertion.

However, we have found examples of fairly recent biology books
showing greatly exaggerated embryonic development, just as Wells
claimed existed. These are based on drawings by Ernst Haeckel, and
were first published 125 years ago. In these drawings, the embryos of
vertebrate species (salamander, human, rabbit, chicken, and fish)
appear to look much more similar than they, in fact, actually
appear.

Haeckel's Embryos

But recent discoveries that many species share developmental genes
have stimulated much new research into comparative embryology, and
this has resulted in the realization that Haeckel's drawings were
severely flawed. A research news article entitled "Haeckel's Embryos:
Fraud Rediscovered," penned by Elizabeth Pennisi, appeared in the 5
September 1997 Science (277, p. 1435). This article pointed to a more
detailed discussion of the distorted embryo drawings in an article by
London embryologist Michael Richardson, which appeared in the August
1997 Anatomy and Embryology. And here is what Richardson himself had
to say on the matter: "A recent study coauthored by several of us and
discussed by Elizabeth Pennisi (Science, 5 Sept. 1997, p. 1435)
examined inaccuracies in embryo drawings published last century by
Ernst Haeckel. Our work has been used in a nationally televised
debate to attack evolutionary theory and to suggest that evolution
cannot explain embryology . We strongly disagree with this viewpoint.
Data from embryology are fully consistent with Darwinian
evolution.... the mixture of similarities and differences among
vertebrate embryos reflects evolutionary change in developmental
mechanisms inherited from a common ancestor... Haeckel's inaccuracies
damage his credibility, but they do not invalidate the mass of
published evidence for Darwinian evolution. Ironically, had Haeckel
drawn the embryos accurately, his first two valid points in favor of
evolution would have been better demonstrated." [Michael K.
Richardson, et al., "Haeckel, Embryos, and Evolution," Science
(Letters), Vol. 280 ( May 15, 1998), pp. 983-985.]

Wells complains that the latest edition of Miller and Levine's
BIOLOGY, one of the most widely used high-school texts, still
contains these flawed diagrams. I contacted one of the book's
authors, Professor Kenneth Miller (Brown University), who responded
that he, after learning of Richardson's work, "... immediately posted
a correction of our 'mistaken' diagrams on the Internet late in 1997,
at http://BioCrs.biomed.brown.edu/Books/Chapters/Ch%2010/Haeckel.htm
" (Personal communication, May 14, 1999). The edition
of Miller and Levine's Biology that Wells criticizes is the 4th
edition, which was actually written before the Richardson paper on
Haeckel appeared in 1997. The latest edition (5th ed., first
published in March of 1999 and bearing a 2000 copyright) has
corrected diagrams, re-printed here with permission.

We encourage everyone curious to see what real vertebrate embryos
of various species (human, chicken, pig, fish) look like during
development to check out the spectacular NOVA episode "Odyssey of
Life" featuring Lennart Nilsson's incredible time-lapsed embryo
micrographs. Links are available at Miller's aforementioned
website.

We agree with Wells that such distortions do no good, and should
be eliminated as quickly as possible from curricular materials. We
also agree with Jonathan Wells' conclusion on the matter, published
recently in an article entitled "Haeckel's Embryos and Evolution:
Setting the Record Straight" (The American Biology Teacher, Vol. 61,
No. 5, May 1999): "This does not mean that students interested in
evolution should be discouraged from studying embryology. On the
contrary, the interface between evolution and development is one of
the most exciting research areas in biology today."

Regarding developmental mutations: A brief literature survey by a
colleague indicated that "saturation mutagenesis" is primarily a tool
employed to find out just which bits of various proteins and/or
enzymes are functional. However, some researchers are employing the
technique to develop improved catalysts. See, for example, "Directed
evolution of industrial enzymes," C. Schmidt-Dannert and F. H.
Arnold, Trends in Biotechnology, 17,135-136 (1999), or "Directed
evolution of biocatalysts," F. H. Arnold and A. A. Volkov, Current
Opinion in Chemical Biology, 3, 54-59 (1999). More details are
available at a Cal Tech website, http://www.che.caltech.edu/groups/fha/Enzyme/Ref-enzyme.html

. The fact that inducing saturated levels of mutations hasn't yet
produced radically different species does not prove that such
developmental processes are impossible in nature (where these
processes require many generations, significant populations, and low
levels of mutation), nor does it prove that such processes are
impossible in the laboratory (it's probably just a matter of a few
years or decades).

Regarding natural selection: Wells claims that "peppered moths...
may be the only good example above the molecular level of a change in
gene frequencies due to natural selection.... in most of the classic
examples of natural selection above the molecular level (e.g.,
Darwin's finches, Hawaiian Drosophila, and the squirrels and lizards
you cite), the genetic basis is unknown." It's true that, until
recently, the actual genetic relationships among Darwin's finches
were not known. But that has changed with the recent publication of
"Phylogeny of Darwin's finches as revealed by mtDNA sequences," Akie
Sato, et. al., Proceedings of the National Academy of Sciences USA,
Vol. 96, pp. 5101--5106, April 1999. In this paper, detailed studies
of the mitochondrial DNA of the 14 recognized species of Darwin's
finches on the Galapagos and Cocos islands confirm what Darwin
hypothesized long before our knowledge of DNA: namely, that the
finches, with their incredible variety of beaks, all arose from a
single common ancestor. The study shows that the Warbler Finch is
closest to the ancestor of the monophyletic group, which was probably
similar to the modern dull-colored grassquit. The vegetarian finches
are another side branch. After their appearance, the main family tree
develops two major branches: the ground finches (six species) and the
tree finches (six species). The Cocos finch is closely related to
tree finches, showing that the Cocos Islands were colonized from the
Galapagos. We encourage Dr. Wells to look into this spectacular
example of change in gene frequencies due to natural selection.